<template>
    <div class="login_container">
        <div class="login_box">
            <!-- 头像区域 -->
            <div class="avatar_box">
                <img src="../assets/logo.jpg" alt="">
            </div>
            <!-- 登录表单区域 -->
            <el-form ref="loginform_ref" :model="login_form" :rules="loginform_rules" class="login_form" >
                <!-- 用户名 -->
                <el-form-item prop="username">
                    <el-input prefix-icon="el-icon-user-solid" v-model="login_form.username"
                    placeholder="请输入用户名"></el-input>
                </el-form-item>
                <!-- 密码 -->
                <el-form-item prop="password">
                    <el-input prefix-icon="el-icon-lock" v-model="login_form.password"
                    placeholder="请输入密码" type="password"></el-input>
                </el-form-item>
                <!-- 按钮 -->
                <el-form-item class="btns">
                    <el-button type="primary" @click="login">登录</el-button>
                    <el-button type="info" @click="reset_loginform">重置</el-button>
                </el-form-item>
            </el-form>
        </div>
    </div>
</template>

<script>
export default {
  data () {
    return {
    // 登录表单的数据绑定对象
      login_form: {
        username: '',
        password: ''
      },
      // 表单的验证规则对象
      loginform_rules: {
        username: [
          { required: true, message: '用户名不能为空', trigger: 'blur' }
          // { min: 3, max: 10, message: '长度在 3 到 10 个字符', trigger: 'blur' }
        ],
        password: [
          { required: true, message: '密码不能为空', trigger: 'blur' }
        ]
      }

    }
  },
  methods: {
    //   点击重置按钮，重置表单
    reset_loginform () {
      this.$refs.loginform_ref.resetFields()
    },
    login () {
      this.$refs.loginform_ref.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.post('login', this.login_form)
        if (res.meta.status !== 200) return this.$message.error('登录失败')
        this.$message.success('登录成功')
        // 1.将登录成功之后的token，保存到客户端的sessionStorage中
        // 1.1 项目中出现了登录之外的API接口，必须在登录之后访问
        // 1.2 token只应在当前网站打开期间生效,所以将token保存在sessionStorage中
        window.sessionStorage.setItem('token', res.data.token)
        // 2.通过编程式导航跳转至后台主页,路由地址是 /home
        this.$router.push('/home')
      })
    }
  }
}
</script>

<style lang="less" scoped>
.login_container{
    background-color: #2b4b6b;
    height: 100%;
}

.login_box{
    width: 450px;
    height: 300px;
    background-color: #fff;
    border-radius: 3px;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%,-50%);

    .avatar_box{
        height: 130px;
        width: 130px;
        border: 1px solid #eee;
        border-radius: 50%;
        padding: 10px;
        box-shadow: 0 0 10px #ddd;
        position: absolute;
        left: 50%;
        transform: translate(-50%,-50%);
        background-color: #fff;
        img{
            width: 100%;
            height: 100%;
            border-radius: 50%;
            background-color: #eee;
        }
    }
}

.login_form{
    position: absolute;
    bottom: 0%;
    width: 100%;
    padding:0 20px;
    box-sizing: border-box;
}

.btns{
    display: flex;
    justify-content: flex-end;
}

</style>
